Engine Miss + SES = CPS?

mottati · 7th March 2005, 08:03

While at sears point this past weekend, under a couple of pretty hard runs, about 20min into a session on the track, i get a pretty heavy miss and an SES light. Oil temp about 240, coolant temp right in the middle (i know that means little), engine very weak, but will rev beyond 4k (so not limp home, right?). I pull into the hot pit, shut off for 20sec or so, re-start and all if fine, no SES, car runs great, back on track...
(i should add, i took a few runs with some students/passengers in c and d run groups, not pushing the car as hard, and no problem with misses/ses)

Happens again, do the same, happens again, do the same. On the drive home, car feels a bit sluggish (maybe i'm just feeling slow after being at the track though) and i think the exhaust tone might sound different (could be mental as i've already been thinking cam sensor). Get home, let car cool, take a drive, all seems fine.

Pull out the Peak, table 18, codes 01, 63 (or b3), C4 and C6.
Code01, i think a red herring. I had the car dynoed a couple months ago, the shop pulled the wrong fuse (they initially pulled 17 and 31, 31 is for fuel pump). Code 01 is fuel pump relay. Maybe meaningless?

Code 63 is some self test thing, so that doesn't sound related (and my car seems to have this code often, without an ses light. If it's b3, that cat efficiency, bank 5-8, still doesn't sound like that'd cause a miss. (and i have new cats).

Codes C4 &6 are misfire, cyl 1 and cyl 3. OK, so i know which cylinders were missing, but why? Wouldn't a CPS throw a cps code?
Any thought's appreciated, i'm CPO, so i'll call the dealer tomorrow, but i'm curious.

kjell · 7th March 2005, 08:26

I just changed intake/exhaust CPS on bank 2 (showed up using Peake) and some gaskets because of oil where the sparks are. I thought everything should be fine, but I still get the exact same problem that you have. It seems ok most of the time, but if I drive it hard, I get the strange exhaust noise and almost no power, restart will fix it. I get misfire on cylinder 1 and 5. I now think it's the MAFs, have tried to clean them twice and seems to help, but will probably buy new ones. Similar problems earlier described in this forum seems to point towards the MAFs.

Rgds,
Kjell

Quote:

Originally Posted by mottati

While at sears point this past weekend, under a couple of pretty hard runs, about 20min into a session on the track, i get a pretty heavy miss and an SES light. Oil temp about 240, coolant temp right in the middle (i know that means little), engine very weak, but will rev beyond 4k (so not limp home, right?). I pull into the hot pit, shut off for 20sec or so, re-start and all if fine, no SES, car runs great, back on track...
(i should add, i took a few runs with some students/passengers in c and d run groups, not pushing the car as hard, and no problem with misses/ses)

Happens again, do the same, happens again, do the same. On the drive home, car feels a bit sluggish (maybe i'm just feeling slow after being at the track though) and i think the exhaust tone might sound different (could be mental as i've already been thinking cam sensor). Get home, let car cool, take a drive, all seems fine.

Pull out the Peak, table 18, codes 01, 63 (or b3), C4 and C6.
Code01, i think a red herring. I had the car dynoed a couple months ago, the shop pulled the wrong fuse (they initially pulled 17 and 31, 31 is for fuel pump). Code 01 is fuel pump relay. Maybe meaningless?

Code 63 is some self test thing, so that doesn't sound related (and my car seems to have this code often, without an ses light. If it's b3, that cat efficiency, bank 5-8, still doesn't sound like that'd cause a miss. (and i have new cats).

Codes C4 &6 are misfire, cyl 1 and cyl 3. OK, so i know which cylinders were missing, but why? Wouldn't a CPS throw a cps code?
Any thought's appreciated, i'm CPO, so i'll call the dealer tomorrow, but i'm curious.

gsfent · 7th March 2005, 15:19

Quote:

Originally Posted by mottati

Happens again, do the same, happens again, do the same. On the drive home, car feels a bit sluggish (maybe i'm just feeling slow after being at the track though) and i think the exhaust tone might sound different (could be mental as i've already been thinking cam sensor). Get home, let car cool, take a drive, all seems fine.

Codes C4 &6 are misfire, cyl 1 and cyl 3. OK, so i know which cylinders were missing, but why? Wouldn't a CPS throw a cps code?
Any thought's appreciated, i'm CPO, so i'll call the dealer tomorrow, but i'm curious.

I had both CPS intakes go at different times. The first one, intermittant SES light. Just before repair, I got solid SES and a throaty sound out of the exhaust. I thought it was my imagination, but not. Second time, SES light, but no noticable sound difference. Both times, I did NOT go into limp mode, but I was only street driving so that may have made some difference.
Regards,
Jerry

mottati · 7th March 2005, 16:20

I've got recent mafs, maybe a year and a half old or so (20k miles), and that was different symptoms for me.

I'm not going into limp home, car will rev beyond 4k, but there is a pretty heavy miss at all rpms. The heat seems to be a factor, if i'm cruising along with the D or C group, no issues, but when i'm really geting on it, it happens.

I've had a vanos unit go bad before, but that did throw the car into limp home, wouldn't reve above 4k etc.

As an aside, the M5 continues to amaze me (and everyone who rides in it!)! My first run on Sat (which was the last a session run of the day) i went out on track with a group of instructors (2 e46 M3s, an e30 race car) and a couple of fast students in 911 GT3's and the M5 was hanging with them for 3-4 laps, until the miss started... I actually got a passing signal from the instructor in the e30 track car (that would have made a great picture)
MIke

2003 M5!!! · 7th March 2005, 16:33

Mottati,

Did you talk to Bill? I wonder what his take is on the miss? Hope all works out . . . It is probably no big deal . . .

P.S. Let us know if you have any warranty issues given the mods.

Take care,

Shawn

Quote:

Originally Posted by mottati

I've got recent mafs, maybe a year and a half old or so (20k miles), and that was different symptoms for me.

I'm not going into limp home, car will rev beyond 4k, but there is a pretty heavy miss at all rpms. The heat seems to be a factor, if i'm cruising along with the D or C group, no issues, but when i'm really geting on it, it happens.

I've had a vanos unit go bad before, but that did throw the car into limp home, wouldn't reve above 4k etc.

As an aside, the M5 continues to amaze me (and everyone who rides in it!)! My first run on Sat (which was the last a session run of the day) i went out on track with a group of instructors (2 e46 M3s, an e30 race car) and a couple of fast students in 911 GT3's and the M5 was hanging with them for 3-4 laps, until the miss started... I actually got a passing signal from the instructor in the e30 track car (that would have made a great picture)
MIke

mottati · 7th March 2005, 18:35

No not at this point. I found another post where it was just a bad plug. I did replace my plugs not long ago, maybe 6k miles, but maybe i have a dud, or a weak coil.
As for the warranty, i have a good relationship with my dealer and SA, so i don't expect any major problems, don't think this is in any way related to the headers.
Mike

Quote:

Originally Posted by 2003 M5!!!

Mottati,

Did you talk to Bill? I wonder what his take is on the miss? Hope all works out . . . It is probably no big deal . . .

P.S. Let us know if you have any warranty issues given the mods.

Take care,

Shawn

2003 M5!!! · 7th March 2005, 18:53

Sounds like you were having fun at the track!

Quote:

Originally Posted by mottati

No not at this point. I found another post where it was just a bad plug. I did replace my plugs not long ago, maybe 6k miles, but maybe i have a dud, or a weak coil.
As for the warranty, i have a good relationship with my dealer and SA, so i don't expect any major problems, don't think this is in any way related to the headers.
Mike

mottati · 8th March 2005, 23:16

OK, well i got a call from my SA. They found 3 fault codes, fuel pump relay (occured once), cat efficiency (occured once) and a misfire on cyl 8 (occured twice) similar but not exactly what my peak tool told me. They also said my adaptations were at the far end of the range, so they would reset them and see what happens. He said not enough to go on to replace any parts yet.... although i did get another valve cover gasket and a radiator cap from my cpo warranty...
I was going to replace my fuel filter, seems like a good idea at 62k but it's special order and i want my car back, so that can wait a couple of weeks!
Mike

gsfent · 8th March 2005, 23:29

Quote:

Originally Posted by mottati

OK, well i got a call from my SA. They found 3 fault codes, fuel pump relay (occured once), cat efficiency (occured once) and a misfire on cyl 8 (occured twice) similar but not exactly what my peak tool told me. weeks!
Mike

I had SES and diagnosis was bad drivers cat (I assume cat efficiency). Car seems to run fine. It is being ordered and replaced under warranty. No hassles.
Regards,
Jerry

gsfent · 8th March 2005, 23:31

Quote:

Originally Posted by mottati

As an aside, the M5 continues to amaze me (and everyone who rides in it!)! My first run on Sat (which was the last a session run of the day) i went out on track with a group of instructors (2 e46 M3s, an e30 race car) and a couple of fast students in 911 GT3's and the M5 was hanging with them for 3-4 laps, until the miss started... I actually got a passing signal from the instructor in the e30 track car (that would have made a great picture)
MIke

Mike
As good as the M5 is, it still needs a good pilot. Give yourself some credit!

Regards,
Jery